Calibrating an FN Tandem Van de Graaff Accelerator using Isotopic Ratios in Monitor Reactions*

Precise calibrations of particle beams are necessary for accurate cross-section measurements, amongst many other important nuclear science applications. The 10 MV FN Tandem Van de Graaff accelerator at the Center for Accelerator Mass Spectrometry (CAMS) facility at Lawrence Livermore National Laboratory was calibrated by comparing produced isotope activity ratios from deuteron-irradiated foil stacks with well-studied monitor reaction cross sections. This method allows independent calibration of the particle beam in order to better inform future experiments which require high precision in incident beam energy. More work is needed due to limitations in experimental design and the available nuclear data, though the method shows promise and a preliminary result calibrates the beam to within ~90keV. Additionally, an alternative method for calibrating the particle beam was developed using existing beam path magnetic field data from previous experiments at the CAMS facility, providing an important cross-check to better inform results from the initial method of calibration.